The present invention relates to a device and method for repairing chipped glass and more particularly to a device and method for repairing and re-repairing a laminated glass, e.g., an automobile windshield, that is chipped by a stone or similar projectile.
The repair of stone-chipped laminated glass is an established art. The financial savings from repairing damaged laminated glass, rather than replacing it, has created a well established market for equipment, materials and new repair methods.
Laminated glass generally consists of three layers. The first and third layers consist of glass panes, which are usually of a safety variety. The second layer is a layer of plastic which separates or is sandwiched between the layers of glass. Generally, if the glass incurs stone-chip damage, usually only the impacted layer of glass is damaged. The stone-chip damage is generally one of two types: (1) a circular or "bulls-eye" break or (2) the so called "star" break which is a break that resembles a star because of its multiple radiating cracks. The impact point of the stone or the projectile on the glass is referred to as "a pit." If the pit is smooth to the touch, it is called a "small" pit. If the pit is rough to the touch because pieces of the fractured glass have been knocked out of the impact point, the pit is then referred to as a "large" pit.
Stone-chipped laminated glass is typically repaired by forcing a repair material, e.g., a liquid resin which has an index of refraction approximately equal to that of the glass, into the break at high pressure. Presently, a windshield repair apparatus supporting an injector which has a means for sealing around the break is utilized to inject the liquid resin into the crack. Such an apparatus is shown in U.S. Pat. No. 3,993,520 and U.S. Pat. No. 4,291,866. Essentially, a windshield repair apparatus comprises a unitary frame assembly which has a plurality of support legs, a suction cup assembly and a crank assembly. The unitary frame further includes a stanchion which supports an injector tube which has a means for sealing at the discharge end or that end of the tube that comes in contact with the glass.
In prior art processes, the repair process begins by probing the pit with a carbide or diamond tip scraper to knock off and flex any excess glass and to make the glass receptive to the resin. In some instances, a very small drill was used to create a small hole into the glass. The depth of the hole was usually slightly greater than the width of the impacted glass layer. If this scraping or drilling was not carefully done, the repair created unwanted additional surface scratches. Commonly, the drill actually entered the plastic layer between the two layers of the glass. The entry into the plastic layer by the drill caused a scar in the plastic which was visible after completion of the repair. In addition, careless scraping or drilling break edges off the pit, thereby leaving repair scars after the repair job is complete.
After the pit was prepped, a repair apparatus was mounted directly onto the glass windshield through the use of suction cups in such a manner that the injector tube was directly over the pit. When the unit was properly aligned, it was sufficiently locked into place so that the pressure necessary to inject the resin did not move the apparatus. The injector tube was then tightened against the windshield so that an adequate seal was formed to maintain the pressure on the injected resin. A syringe inserted into the injector tube injected the repair resin into the break. After an adequate amount of resin has injected, the syringe was withdrawn and a manual pump was inserted into the injector tube. As the pump is driven into the injector tube, a positive pressure was exerted on the resin, forcing the resin into the cracks of the break. As the pump was withdrawn a negative pressure was created which drew air pockets of the break. The repeated insertion and removal of the pump into and out of the injector tube eventually drew all of the air out of the break.
One drawback with the old method of repairing laminated glass, however, was that the repairer could not readily determine when the cracks of the break were completely filled with resin. This determination was further hampered by the fact that the repairer worked under an ultraviolet inhibitor or cover because most resins harden when subject to ultraviolet radiation. Consequently, the quality of the repair of the glass was often unsatisfactory and/or required break of the repair to be repaired again. Both scenarios evidence the relative inefficiency of repairing automobile windshield, or laminated glass in general, by the old method.
It would be highly advantageous therefore, to remedy the foregoing and other deficiencies and inherent limitations associated with the apparatus and method for repairing a star or bull's-eye crack in automobile windshields.
Accordingly, it is a principal object of the present invention to provide the repair person a means for providing a reference to determine the extent the repair resin or material fills the cracks of the break. A further object of the present invention is to allow the progress of the repair to be better monitored and quickly give the repair person indications as to any part of the break that is not accepting the repair process so that proper measures can be implemented for the speedy completion of the break.
It is a further object of the present invention to provide the repair person with a means for preventing additional scratches or scars when the pit is being prepared.
It is a further object of the present invention to provide a nozzle adapter that adapts to the injector tube that has reference indicators or a series of regular markings that provide a reference to determine the extent the repair resins fills the cracks of the break.
A further object of the present invention is to provide different sized nozzle adapters that can be used for repairing small pit repair and/or converted to repairing large pits. It is a further object of the present invention to provide a nozzle adapter that hold specialized tools in such a firm fashion as to not allow them to break down the edges of the pit and/or cause additional scratches.
It is a further object of the present invention to employ an inspection mirror that magnifies the break, thereby giving the repair person a better vantage point and view of the progress of the repair, thus facilitating a more effective and efficient repair.
It is a principal object of the present invention to provide a new method for repairing laminated glass by utilizing a nozzle adapter having a tool guide for guiding specialized tools that aids the repair person in the preparation of repairing a break of a laminated glass. It is another principal object of the present invention to provide a method for re-repairing laminated glass or windshields that were previously poorly repaired or whose resin material has caused blemishes or scars in the windshield.
It is a further feature of the present invention to provide a conduit for repair resin materials to flow into the break under hydraulic pressure created by the pump. It is a further feature of the present invention to provide injector tube nozzle adapters of different dimensions in order to repair large pits or small pits at the very edges of automobile windshields or on the curved portion of automobile windshields. It is an advantage of the present invention to provide a nozzle adapter that facilitates as a platform for the insertion of specialized tools to repair the pit without creating further scratches or breaks in the edge of the pit. It is a further feature of the present invention to use a magnifying mirror that permits the repairer to determine whether the trailing edges of cracks that are difficult to see by the naked eye are being filled up with repair resin.
The foregoing and more specific objects, the advantages and features of the present invention will become readily apparent to those skilled in the art in the following detailed description of the preferred embodiments and methods thereof taken in conjunction with the drawings.